package reflect;

public class Rectangle {
    private int length;
    private int width;
    private Rectangle() {}
    private Rectangle(int length, int width) {
        this.length = length;
        this.width = width;
    }
    /**
     * 定义一个计算矩形周长的方法
     * @return
     */
    public int getPerimeter() {
        return 2 * (length + width);
    }
}
